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of the Commonwealth of Pennsylvania

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    Pennsylvania Standards Laboratory

    The Pennsylvania Standards Laboratory (PSL) provides metrological traceable calibrations of artifacts relating to mass, volume, length, time and force. The services below are available to the weights and measures community, private industry, service companies, municipal governments, and other state government agencies.   

    • Advanced calibration of mass standards from 30 kg to 1 mg, 1000 lb to 0.001 lb and 8 oz to 1/32 oz.   
    • Medium accuracy calibration of mass standards from 2500 kg to 1 mg, 5000 lb to 0.001 lb, 12 oz to 0.01 oz, 200 oz t to 0.005 oz t and 1000 gr to 0.1 gr.
    • Calibration of weight carts from 6000 lb to 3000 lb.   
    • Calibration of Class IIII scales (wheel-load weighers) up to 40 000 lb.
    • Gravimetric calibrations of volumetric standards from 120 gallon to 1 gallon, 5 gallon (Imperial) and 500 liter to 5 liter.  
    • Calibration by volume transfer method of neck-type metal provers from 1500 gallon to 5 gallon and 5000 liter to 20 liter. 
    • Length calibrations of steel tapes up to 200 ft. 
    • Stopwatch and timer calibrations up to 24 hour.
    • Force calibrations of push-pull gauges by tension up to 30 lbf. 

    Class IIII Scale (Wheel Load Weigher) Calibration

    The Pennsylvania State Police, Pennsylvania Department of Transportation and many municipal governments throughout the Commonwealth have vehicle weight enforcement programs. The PSL requires the use of National Type Evaluation Program (NTEP) approved Class IIII Scales (Wheel Load Weighers). Title 75 Pa C.S.A. requires these scales to be certified annually (or following an event that could affect the accuracy or following repairs or failures) by the Pennsylvania Department of General Services. These calibrations are conducted by appointment at the Pennsylvania Standards Laboratory.  

    Forms & Resources  

    New - Public Fee Schedule establishes fees for calibration services. All local (including municipal police departments), state and federal government agencies are exempt from fee payments.  

    Schedule Request Form may be used to request a date for scheduling calibration at the Pennsylvania Standards Laboratory. Completed forms can be faxed or emailed to the PSL. 

    Bio Medical Cleanliness Form must accompany items that have been exposed to any hazardous substance to ensure items are safe for human handling. 

    Preparation of Large Volume Provers Form must accompany any provers (1500 gallon/500 liter to 25 gallon/100 liter) that are submitted for calibration to document that the prover has been cleaned and is free from any petroleum products or residue before the start of the calibration.  

    Submission Requirements Cast Iron Weights provides recommendations for the cleaning and painting of weights. Although not required to be painted before submission, the condition of weights should be evaluated before submitting them for calibration. Cast iron weights that are not free from foreign matter such as dirt, rust, grease, concrete or asphalt will not be calibrated.

    Submission Requirements Test Measures provides the criteria that must be met before your volume measures will be calibrated.

    Pennsylvania Standards Laboratory 

    2221 Forster Street, Room G-44A
    Harrisburg, PA 17125
    Phone: (717) 787-0937
    Fax: (717) 705-0882

    PSL hours of operation are Monday-Friday, 7:30 AM - 3:30 PM (closed 12:00 - 12:30 for lunch). All calibrations are by appointment and must be scheduled in advance. Delivery or pick-up should be arranged within business hours. 

    PSL National Institute of Standards and Technology (NIST) Certificates 

    NIST-Office  of  Weights  and  Measures  Certificate  of Metrological Traceability ​

    NIST - National Voluntary Laboratory Accreditation Program (NVLAP)  Certificate of Accreditation to ISO/IEC 17025:2017 

    NVLAP LAB CODE 200869-0 

    NIST - National Voluntary Laboratory Accreditation Program (NVLAP) Scope of Accreditation to ISO/IEC 17025:2017 ​

    NVLAP LAB CODE 200869-0